The use of lighting units to simulate daylight or skylight is known in the art. WO2013011410, for instance, describes a lighting element used for obtaining a skylight appearance, which comprises a white light emitting means for emitting white light, a blue light emitting means for emitting blue light and a Fresnel lens. The Fresnel lens is arranged to receive light from the white light emitting means and from the blue light emitting means. The white light emitting means is arranged in a first relative position with respect to the Fresnel lens to collimate at least a part of the light emitted by the white light emitting means to obtain a collimated directed light beam in a specific direction. The blue light emitting means is arranged in a second relative position with respect to the Fresnel lens to obtain a blue light emission at least outside the collimated directed light beam.